1. Field of the Invention
The present invention relates to valve devices used in connection with tapping points from metallurgical containers.
In casting operations it would be of great value to have a signal indicating when the surface of the bath has declined to the point that slag starts streaming out from the tap hole. A vortex is normally formed above the tap hole and sucks down the slag from the surface of the bath, and therefore considerable amounts of slag are suddenly drawn down into the tap stream. The requirements for accuracy of the measurement signal from a slag indicator are therefore moderate.